Microsoft never sleeps. Even before the Windows 10 April 2018 Update (version 1803) started to roll out, the company began work on the next major update to Windows 10, code-named Redstone 5 and due to be released this autumn. As it did with the April 2018 Update, Microsoft has been releasing a series of public preview builds to members of Microsoft's Insider Program.

What follows is a list of every preview build of Redstone 5, starting with the most recent. For each build, we've included the date of its release, a summary of what’s in the build and a link to Microsoft's announcement about it. After that you’ll find summaries of all the preview builds that led up to the Windows 10 April 2018 Update (Redstone 4), the Windows 10 Fall Creators Update (Redstone 3) and the Windows 10 Creators Update (Redstone 2).

Note: If you're looking for information about updates being rolled out to all Windows 10 users, not previews for Microsoft Insiders, see "Windows 10: A guide to the updates."

Windows 10 Insider Preview Build 17738

Release date: August 14, 2018

This very minor build introduces no new features. It has more than a dozen bug fixes and minor changes and improvements, including fixing an issue that hurt the Start menu’s performance and reliability, and another in which Microsoft Edge’s Settings and More menu became truncated when the option to increase text size was enabled in Settings.

There are a half-dozen known issues in this build, including one in which a PC will perform a bug check (GSOD) when deleting a local folder that is synced to OneDrive, and another in which after setting up a Windows Mixed Reality headset for the first time with motion controllers, the controllers may need to be paired a second time before appearing in the headset.

Windows 10 Insider Preview Build 17735

Release date: Aug. 10, 2018

This very minor build introduces no new features, and has fewer than a dozen bug fixes and minor changes and improvements, including fixing an issue in which links that launched one app from another app were not working, and another in which in Windows Mixed Reality the voice command, “Flashlight on,” would fail to activate the flashlight feature.

There are a number of known issues in this build, including your PC performing a bugcheck (GSOD) when deleting a local folder that is synced to OneDrive, and another in which the taskbar flyouts (network, volume, etc.) no longer have an acrylic background.

Windows 10 Insider Preview Build 17733

Release date: Aug. 8, 2018

This very minor build introduces only one very small feature, a dark theme in File Explorer. In addition, Narrator received more than a dozen fixes, including one in which Narrator couldn’t access all the emoji in the Touch Keyboard’s emoji panel, and another in which Narrator couldn’t read the label of the Word document recovery dialog. A few overall fixes were also made for Windows 10 itself, including one in which the touch keyboard became invisible on the screen, and another in which – if you reset certain devices and chose to keep files – the Sound Settings page would be unresponsive after logging back into Windows.

There are a number of known issues in this build, including potential Start reliability and performance issues, and one in which after setting up a Windows Mixed Reality headset for the first time with motion controllers, the controllers may need to be re-paired a second time before appearing in the headset.

Windows 10 Insider Preview Build 17730

Release date: Aug. 3, 2018

This build introduces the new Your Phone App that will let people with Android phones see and copy photos from those phones to their PCs. To install it, click the Your Phone app icon, and you’ll then get an app that has to be installed on the phone. The iOS version links an iPhone to a PC, so that when you surf the web on your phone, you’ll be able to send the webpage to your PC and pick up where you left off on the phone.

In addition, there are the usual small changes and fixes, including resolving an issue that caused the volume slider in certain apps to perform poorly with touch, and another in which in certain apps, including Twitter, stopped rendering content when navigating after a while.

There are a number of known issues in this build, including one in which clicking a link to launch one app from another app may not work, and potential Start reliability and performance issues.

Windows 10 Insider Preview Build 17728

Release date: July 31, 2018

This minor build makes a number of changes to the Narrator, including better reading and navigating in Scan mode, improved reliability, and better use of Braille commanding when using the Narrator key from the Braille display.

Microsoft also announced that in the next few weeks, Windows Insiders will be able to use the new Your Phone App to let people with Android devices see content from those devices on their PCs. It will do things such as let someone take pictures on an Android phone and then view the photos on a PC. The app will let users with iOS devices link their phones to their PCs to do things such as surf the web on their phones, then send the webpage to their PCs so they can pick up where they left off.

In addition, there are the usual small changes and fixes, including an issue in which the Clock & Calendar flyout sometimes did not appear until the Start or the Action Center was clicked, and another in which Find on Page in Microsoft Edge would stop working for open PDFs once the PDF was refreshed.

There are a number of known issues in this build, including one that affects WDAG, Remote Desktop and Hyper-V. In it, Remote Desktop Client (mstsc.exe) users will see a misleading error dialog warning about low virtual memory when a connection is being established.

Windows 10 Insider Preview Builds 17723 and 18204

Release date: July 25, 2018

This build serves double-duty. It’s both a preview (17723) for Redstone 5 as well as the first build for testers (18204) who have opted into Skip Ahead for Redstone 6.

Emoji fans will be pleased to see that there are now 157 new emoji, including superheroes, redheads, a softball, a pirate flag and a llama. That’s because Unicode 11 has been incorporated into the build. Access them via the Emoji Panel (WIN + .) or the touch keyboard.

Also new is what Microsoft is calling a mixed reality flashlight, which lets you easily bypass the mixed reality world when you’re wearing a mixed reality headset, and instead look at the real world. So no longer will you have to remove your headset when you want to peek at something nearby or reach for a drink or phone, for example. You’ll be able to do it via the Start menu, a button shortcut or a voice command.

Microsoft Edge has gotten a few tweaks, including new Group Policies and MDM settings for IT administrators to manage it. There’s also an easier way for device administrators to set up their PCs as a kiosk or digital sign.

In addition, there are a variety of small changes and fixes, including one in which some laptops underwent a CRITICAL PROCESS DIED bug check when the PC was put to sleep by closing the lid and the connected power disconnected. There are also a variety of known issues, including one in which the clock & calendar flyout may not appear until bringing up Start or Action Center, and they will then both appear at the same time. The same issue may result in notifications not appearing until Start or Action Center is opened.

Windows 10 Insider Preview Build 17711

Release date: July 6, 2018

No big news in this build. Microsoft Edge gets a few minor additions, including new themes and a new consent box for saving autofill data. Microsoft also continues to add new Fluent design elements throughout Windows, including shadows for popup controls. There’s also a new Windows HD Color page, available under Display Settings. The Registry Editor has been improved with more useful input tools.

There is also a wide variety of very small fixes, including for a bug in which attempting to pin Settings categories to the Start menu would either crash Settings or do nothing, and another in which creating a system image from backup and restore in the control panel would fail on x86 machines.

Windows 10 Insider Preview Build 17704

Release date: June 27, 2018

The big news in this build is that the Sets feature, which lets you group documents, web pages, files and apps in tabs, and then work with them, has been pulled — with no word about when it might be reinstated. This means that it may not ship with Redstone 5.

Sets was originally scheduled to be released as part of the Windows 10 April 2018 Update (Redstone 4), but Microsoft pulled it due to a variety of problems. The company included Sets in Redstone 5 builds starting with Build 17618 on March 7, 2018 — even before the Windows 10 April 2018 Update was released. And now, in Build 17704, Microsoft has pulled it again.

Microsoft explained the decision this way in its description of this latest build: “Starting with this build, we’re taking Sets offline to continue making it great. Based on your feedback, some of the things we’re focusing on include improvements to the visual design and continuing to better integrate Office and Microsoft Edge into Sets to enhance workflow. If you have been testing Sets, you will no longer see it as of today’s build, however, Sets will return in a future WIP flight.”

No date was set for the feature’s return, so there’s no guarantee it will be included in Redstone 5, due this fall. If you’ve been following the build notes for Redstone 5, you might not be that surprised about what Microsoft has done, because Microsoft has continually reported issues with the feature in its notes about each build.

Aside from pulling Sets, Microsoft has done a fair amount of work on Microsoft Edge in this build, including incorporating more Fluent Design elements into it, adding redesigned settings and the ability to customize the toolbar, as well as giving users control over whether media should automatically play on web pages.

The Skype for Windows 10 app gets a serious update with a variety of new features, including easier screen sharing, a new layout making it easier to find contacts, customizable themes and more. Check here for more details from Microsoft.

The Diagnostic Data Viewer, available as a separate download, has gotten tweaks, including the ability to view problem reports that have been or will be sent to Microsoft. However, it remains an extremely difficult-to-use tool that even programmers will struggle to understand.

There have also been a several improvements to Windows Security, including new protections and settings such as to block suspicious behaviors and to manage the various types of anti-malware, firewall and other security software running on your PC.

Other changes include allowing non-admin users to install fonts, and new columns for Task Manager that show power usage and power trends. There is also a long list of fixes, including for a bug that caused the lock screen to crash in a loop when Picture Password was selected, and another in which when Cortana search results were clicked, nothing would happen.

And there are a small number of known issues, including one in which Windows Mixed Reality might get stuck after going to sleep and display an error message in Mixed Reality Portal or a “Wake up” button that doesn’t work.

Windows 10 Insider Preview Build 17692

Release date: June 14, 2018

This build introduces an easier way to use the Windows 10 touchscreen keyboard with the addition of SwiftKey, which lets you enter text by dragging your fingers. SwiftKey, previously available only for iOS and Android, also improves the accuracy of autocorrections and text-input predictions.

In addition, there have been improvements to a number of Windows features. You can now search for text using Narrator’s new Find feature, and Narrator will also automatically read the contents of a dialog box when brought to the foreground, among other additions. New audio controls have been added to the Game Bar that let you change your default audio output device and mute or adjust the volume of games and apps running. Windows Mixed Reality has gotten several improvements, including the ability to stream audio to both a headset and PC speakers simultaneously.

There are the usual variety of minor changes and fixes, including for a bug that resulted in audio glitching on systems with lots of firewall rules, and another in Microsoft Edge where if both images and text were selected, right-clicking on the image and selecting copy wouldn’t work.

There is a long list of known issues with this release, including one in which launching Start causes reliability and performance issues, and another in which some settings in Settings may be unexpectedly missing and/or missing their labels. The Game Bar may also crash on x86 machines.

Windows 10 Insider Preview Build 17686

Release date: June 6, 2018

This minor build makes several minor improvements to Windows Mixed Reality, including adjustments to the mixed reality video capture experience to make it easier to stop videos from the Start menu. Also, the Windows Settings app gets a new Region page that lets you override default regional format settings such as Calendar, First day of the week, Dates, Times, and Currency. To use it, go to Settings > Time & Language > Region.

There are the usual variety of minor changes and fixes, including one in which Paint and WordPad settings and recent files weren’t migrated during upgrades, and another in which taskbar flyouts (network, volume, etc.) didn’t have a shadow. There are also a number of known issues that haven’t been fixed, including increased reliability and performance issues when launching Start. The new Sets feature continues to have problems working with Microsoft Office; for instance, there’s a bug in which tiling and cascading windows, including features like “View Side by Side” in Word, will not work for inactive tabs.

Windows 10 Insider Preview Build 17682

Release date: May 31, 2018

This build includes several minor changes, notably to the new Sets feature. Microsoft has tweaked Sets’ tab page to make it more obvious that apps can be launched from it. Now, when you click the plus button in a Sets window, apps will be included in the frequent destinations list. The “all apps” list has also been integrated into the page so you can browse your apps, instead of having to use the search box.

Microsoft Edge now includes a preview of the new Web Authentication API for developers, which provides an open, scalable and interoperable solution for authentication, and replaces passwords.

Wireless projection gets some tweaks designed to help you know when you’re wirelessly projecting and how to disconnect, particularly if your session was begun in File Explorer or an app. A new control banner at the top of the screen tells you the state of your connection and allows you to quickly disconnect or reconnect. You can also use it to tune the connection based on what you are doing.

There’s the usual variety of minor changes and fixes, including fixing an issue that resulted in some apps missing pinned and recent items when you right-clicked their icons in the taskbar. There are also a number of known issues that have yet to be fixed, including reliability and performance issues when launching Start. The new Sets feature continues to have a variety of problems working with Microsoft Office, many of which have also been present in past builds, including one in which the top of some Win32 desktop app windows may appear slightly underneath the tab bar when maximized. To work around the issue, restore and re-maximize the window.

Windows 10 Insider Preview Build 17677

Release date: May 24, 2018

This build includes a variety of minor changes. Microsoft Edge’s “Settings and more” menu has been reorganized into groups to make options easier to find, and with icons placed next to each menu option. You can now also see your most visited sites on the Windows taskbar or Start menu. Right-click the Microsoft Edge icon to see a list of most visited sites and pin any you want. Right-click on an entry to remove it from the list. You can also more easily organize groups of tabs. In addition, new options (“Show in folder” and “Copy link”) have been added to the right-click menu for downloads in the “Downloads” pane.

The Windows Narrator has been improved and supports selecting content in Edge, Word, Outlook, Mail and most text applications. Mobile Broadband (LTE) connectivity on Windows gets a makeover in this build, and includes a new, more reliable network driver model. In addition, Task Manager’s memory reporting has been improved, and the Windows kernel now has support for IPv6 to KDNET.

There are several minor fixes, including for a bug in which the Home and End keys did not work in Edge. The build also has a variety of known issues, including one in which if you right-click apps in the taskbar, you might find that the jump list is missing pinned and recent items. And the new Sets feature has a variety of problems working with Microsoft Office, including one in which the top of some Win32 desktop app windows may appear slightly underneath the tab bar when maximized. To work around the issue, restore and re-maximize the window.

Windows 10 Insider Preview Build 17672

Release date: May 16, 2018

This build has only very minor changes and fixes. In it, the Windows Security Center (WSC) service now requires that third-party antivirus programs run as protected processes, or else they won’t show up in the Windows Security interface, and Windows Defender Antivirus will run side by side with them. You can, however, disable the behavior by creating the following registry key and rebooting:

Note that the key won’t work when the next version of Windows 10 is closer to being released.

There’s also a variety of minor changes and fixes, including one in which PCs appeared to be stuck at “Preparing to install…” between 80% and 100% in Windows Update when attempting to install a new build.

The build has a variety of known issues, including one in which Narrator reads extra text when Alt + Tab is pressed. And the new Sets feature has a variety of problems working with Microsoft Office, including one in which tiling and cascading windows will not work for inactive tabs.

Windows 10 Insider Preview Build 17666

Release date: May 9, 2018

This build adds a variety of new features, including additions to the Sets feature. Sets now uses more Fluent Design standards, including an acrylic title bar. You can also mute web pages in Sets that play audio. And using Alt -Tab will show all recent Edge tabs when you switch between apps, not just the active one.

Windows Clipboard has been powered up. You can now paste previous items from the Clipboard’s history. And your Clipboard will roam across all of your devices, so you can clip items from a device other than the one you’re currently using.

There are a variety of other improvements, including the addition of a dark theme to File Explorer and improved search. A variety of bugs have been fixed, including one in which the VPN wasn’t working, and another in which a .dll would cause explorer.exe to crash every few minutes. There are, however, a number of known issues, including one in which your PC appears to be stuck on “Preparing to install” when it gets to 80% to 100% of updating. It will take 30 minutes or more to complete the installation from that point.

This build adds a variety of new features, including tweaks to screen capture in Windows 10. Screen Sketch, which lets you annotate screen captures and was originally part of Windows Ink, is now its own app. In addition, pressing WIN + Shift + S brings up a toolbar that lets you capture a rectangle, free-form snip or the entire screen. (In the current version of Windows, that key combination only lets you capture a rectangle.) You’ll also get a notification that, when clicked on, lets you open the snip in Screen Sketch for annotation and sharing.

There are a number of other minor improvements, including one in which Microsoft’s Fluent Design is being extended to Task View, whose background gets a new soft blur look. This build also adds to support for the High Efficiency Image File Format (HEIF), introduced in Build 17623, and lets you do things such as rotate HEIF images.

There’s also the usual assortment of changes and fixes, including fixing an issue in which using arrow and Page Up / Page Down keys didn’t work to scroll webpages in Microsoft Edge. There are a number of known issues with this build, including one in which some notifications from Action Center may cause regular Explorer.exe crashes.

Windows 10 Insider Preview Build 17655

Release date: April 25, 2018

This extremely minor build has only one new feature: Mobile Broadband (LTE) connectivity on Windows is getting a makeover. Microsoft says that its new Net Adapter framework “introduces a new, more reliable, network driver model that inherits the goodness of the Windows driver framework while bringing an accelerated data path.” Only PCs that support Mobile Broadband — that is, use cellular networks — will use the new framework.

Aside from that, there are only two changes and fixes. The brightness toggle in the Battery flyout in the Notification Area of the taskbar has been removed. Microsoft says that will make for an improved user experience. The build also fixes in issue in which Microsoft Edge didn’t work when dragging a favorite from one folder to another.

There are a variety of known issues in this build, including one in which the mouse cursor may disappear when hovering over certain user interface elements and text fields, and another in which the arrow and Page Up / Page Down keys don’t work to scroll web pages in Microsoft Edge. There are also a variety of issues with the new Sets feature, and with Microsoft Office working properly with this build.

Windows 10 Insider Preview Build 17650

Release date: April 19, 2018

This very minor build gives the Windows Defender Security Center a design refresh using Microsoft’s Fluent Design elements, including adjusting the spacing and padding around it and dynamically sizing the categories on the main page if more room is needed for extra info. In addition, the Windows Defender Firewall now supports Windows Subsystem for Linux (WSL) processes.

There’s also the usual assortment of changes and fixes, including an issue in which File Explorer would always open with the Ribbon minimized, rather than remembering how you’d left it. There are a number of known issues with this build, including one in which when a PC resumes from sleep, the desktop may be momentarily visible before the lock screen displays as expected.

Windows 10 Insider Preview Build 17643

Release date: April 12, 2018

This minor build introduces integration between the Microsoft Office and the new Sets feature that lets you group documents, web pages, files and apps in tabs, and then work with them. In addition, if you use a SIM on a mobile device, it will tell you how much data you use while you’re roaming. There are also the usual improvements and fixes, including fixing an issue in which Reveal would sometimes not appear if you moved your mouse over and off an element repeatedly, and another in which there was noticeable screen flicker when the screen adjusts after a device is rotated.

There are number of known issues with this build, including one in which if you open Settings and click on any links to the Microsoft Store or links in tips, Settings will crash, and another in which when a computer resumes from sleep, the desktop may be momentarily visible before the Lock screen displays as expected.

Windows 10 Insider Preview Build 17639

Release date: April 4, 2018

The big news in this build is the new features added to the Sets tool that let you group documents, web pages, files and apps in tabs, and then work with them. You can now drag and drop apps between tabs and use Alt + Tab to switch between tabs. Sets also gets its own section in Settings, available via Settings > System > Multitasking. There are also new context menu options when you right-click on a tab set, including “close other tabs,” “move to new window” and “close tabs to the right.”

Beyond that there’s an assortment of changes, improvements and fixes, including a fix for an issue that caused duplicate entries in Disk Management, and one in which some Windows apps silently terminated when minimized.

There are several known issues with this build, including one in which if you open the Settings app and click any links to the Microsoft Store or links in tips, Settings will crash.

Windows 10 Insider Preview Build 17634

Release date: March 29, 2018

In this build, search is now available in the Windows 10 calendar. You can search by name, location, people included, or words in the event body. It works for Outlook, Hotmail, Live and Office 365 accounts, but not yet Exchange Server, Gmail, Yahoo or other IMAP calendars. In the build, Cortana Show Me supports voice commands, such as for updating Windows, uninstalling an app, discovering Bluetooth devices and more. There is also an assortment of minor fixes and improvements, including for a bug in which Microsoft Edge could crash when certain extensions were turned off, and another in which typing in the Microsoft Edge URL bar immediately after opening a new tab sometimes resulted in the letters appearing out of order.

Windows 10 Insider Preview Build 17627

Release date: March 21, 2018

This very minor build includes only small bug fixes, including for one in which an emoji panel wasn’t working, and another where if you tried to open an online-only file from OneDrive that hadn’t been previously downloaded to your PC, your PC might perform a bug check.

Windows 10 Insider Preview Build 17623

Release date: March 16, 2018

This build rolls out the High Efficiency Image File Format (HEIF), a container that uses modern codecs like HEVC to improve image quality, compression and capabilities compared to earlier formats like JPEG, GIF and PNG. In addition to single images, HEIF supports encoding image sequences, image collections, auxiliary images like alpha or depth maps, live images and video, audio, and HDR. The Windows Defender Application Guard (WDAG) also gets performance improvements.

There are also the usual minor changes and fixes, including for an issue that crashed the touch keyboard when focus was moved to certain password fields, and another in which touch couldn’t be used to interact with the Timeline scrollbar.

Windows 10 Insider Preview Build 17618

Release date: March 7, 2018

This preview reintroduces a major new Windows 10 feature, Sets, that lets you group webpages, documents, files and applications on individual tabs in Windows Explorer. (Sets made a brief appearance in the preview builds for the April 2018 Update but was pulled because it wasn’t ready for general release.) Apps such as Mail, Calendar, OneNote, MSN News, Windows and Microsoft Edge can be grouped. Microsoft says support for more apps will come in the future.

Windows Mixed Reality is buggy in this build. Microsoft notes that it “runs at a very low frame rate (8-10fps) that could result in some physical discomfort. And there are multiple crashes at startup that will cause Windows Mixed Reality to not work.”

There are also the usual minor changes, improvements and fixes, including for a bug in which three- and four-finger gestures on the touchpad were unresponsive, and another in which navigating to Themes Settings crashed Settings.

Windows 10 Insider Preview Build 17604

Release date: February 14, 2018

This is the first preview for Redstone 5, and includes no new features — it’s essentially the same as the Preview Build 17101 for Redstone 4. However, Microsoft warns that this and other early Redstone 5 builds may be buggy, and adds, “So, things will likely be a little rough as they normally are at the beginning of the development cycle for a new Windows 10 release. If this concerns you or makes you uncomfortable, you may want to consider opting out of Skip Ahead.”

Preview builds for the Windows 10 April 2018 Update (Redstone 4, version 1803)

Windows 10 Insider Preview Build 17134

Release date: April 16, 2018

This build fixes problems Microsoft discovered just prior to its planned rollout of Redstone 4. According to Dona Sarkar, head of the Windows Insider Program, the company discovered reliablity issues that could have led to Blue Screens of Death in some cases. "Instead of creating a Cumulative Update package to service these issues, we decided to create a new build with the fixes included," Sarkar wrote in a blog post.

Windows 10 Insider Preview Build 17133

Release date: March 27, 2018; updated April 10, 2018

Note: The final version of Redstone 4 was expected to begin rolling out to the public on April 10, but that didn't happen. Industry watchers believe the company discovered a bug severe enough to prevent the release.

Instead, Microsoft on April 10 released an update to 17133, called Insider Preview Build 17133.73, to Insiders in the Fast, Slow, and Release Preview rings. The build issues security updates to Internet Explorer, Edge, Microsoft scripting engine, Windows kernel, Microsoft graphics component, Windows Server, Windows cryptography, and Windows datacenter networking and squashes a final few bugs, including a PDF security issue in Edge and a glitch in IE's identification of custom controls, before the spring feature update is released.

The scarcity of changes in this latest build shows that the release of Redstone 4 is likely very close. It has fixes for only three small issues: One in which certain devices with BitLocker enabled unexpectedly booted into BitLocker recovery; another in which the display resolution couldn’t be changed when there were four or more monitors connected; and another in which clicking suggested search terms when typing in the Microsoft Edge URL bar didn’t do anything. There are no known issues in this build. Microsoft notes: “We are in the phase of checking in final code to prepare for the final release.”

Windows 10 Insider Preview Build 17128

Release date: March 23, 2018

With this build, Microsoft seems to be getting exceedingly close to the final version of the next major update to Windows 10. The only difference between it and the previous build, 17127, is that the watermark at the lower right-hand corner of the desktop has disappeared. This is frequently a sign that a build is the final one, but Microsoft says that’s not the case this time, noting that “This does not mean this is the final build as we are not done yet...we’ve got more fixes being checked in for the next flight.” However, Microsoft also writes that “We’re just now beginning the phase of checking in final code to prepare for the final release.”

Windows 10 Insider Preview Build 17127

Release date: March 20, 2018

The main additions in this build are some minor changes to Cortana. It now has a profile page where you can add and edit your favorite places. When you add a place, you’ll get traffic updates for your commutes, and be able to quickly set reminders for when you arrive at or leave places. Microsoft also claims that Cortana’s notebook feature has been sped up. Also, when you want to add new skills to Cortana, you’ll get suggested questions on the best ways to add them.

There are also the usual variety of changes, improvements and fixes, although this time around it’s a small list. Included is fixing a problem that caused Microsoft Edge to crash when turning off certain extensions, and another in which the page up and page down keys weren’t working when using Microsoft Edge in Reading View.

Windows 10 Insider Preview Build 17123

Release date: March 16, 2018

Little has changed with this latest build, as the release of the next major update to Windows 10 gets closer. The Windows 10 Photos app now supports the High Efficiency Image File Format (HEIF), which uses new codecs such as HEVC and which Microsoft says offers superior compression and features than older formats such as JPEG, GIF and PNG. To see it in action, you’ll have to join the Windows App Preview Program for the Photos app and be running the March release of the Photos app (Version 2018.18022.13740.0 or newer).

Microsoft continues to squash bugs with Windows Mixed Reality, including making sure that launching the Microsoft Store from Movies & TV no longer crashes either app. It’s also trying to fix other problems with Windows Mixed Reality, including looking into whether it experiences a performance regression on hybrid laptops.

In addition, there are a few very minor changes and fixes, including for a bug in which some older drives didn’t load properly.

Windows 10 Insider Preview Build 17120

Release date: March 13, 2018

The march towards the release of the Windows 10 Spring Creators Update (the likely name for the next big Windows 10 upgrade) continues with another minor build. It includes some small changes to Windows Defender Application Guard (WDAG). Microsoft says its performance has been significantly improved, including faster loading times. It also now allows enterprise users to download files when using the Edge browser in a WDAG browsing session.

The notes for the release also point out that new Windows Mixed Reality features added in the previous build, 17115, have a variety of bugs, including poor performance on hybrid laptops and the 360 viewer failing to launch from the Store app when you click on the “Launch” button after installing the 360 Viewer Edge extension.

In addition, there are a variety of very minor changes and bug fixes, including for one in which the UAC dialog did not render correctly in the last several builds, and another in which the touch keyboard crashed when focus was moved to certain password fields.

In addition, there are a variety of very minor changes and bug fixes, including for one in which the Microsoft Store might be completely broken or gone after upgrading, and another in which at the first user-prompted reboot or shut-down after installation, in a small number of devices Windows 10 didn’t load properly and entered a reboot loop state.

Windows 10 Insider Preview Build 17112

Release date: March 2, 2018

This build is another in Microsoft’s sprint towards the final release of the next major Windows update. It includes no new features, only a variety of minor bug fixes, including for one in which you got a permanently black window if you dragged a tab out of a Microsoft Edge window, pulled it to the top edge of the screen, moved it back down and then released it.

Be warned, however: The build introduces serious problems with running Windows Mixed Reality. Microsoft reports that in this build, “Windows Mixed Reality runs at a very low frame rate (8-10fps) that could result in some physical discomfort. And there are multiple crashes at startup that will cause Windows Mixed Reality to not work.” Microsoft suggests that those who want to pause Insider Builds until the issues are fixed should go to Settings > Update & Security > Windows Insider Program, click the “Stop Insider Preview builds” button and choose “Pause updates for a bit.”

Other known issues with this build include one in which the Microsoft Store may disappear or be completely broken. Microsoft has posted a workaround to fix the problem.

This build focuses primarily on minor improvements for enterprise customers. In it, enterprises can now run custom actions during Windows 10 feature updates, allowing them to customize installations. Setup allows the actions to be run during the pre-install phase, which happens before all the system and device compatibility scans run, and also during the pre-commit phase, just before the system reboots into the offline phase. Setup will also migrate the scripts for future updates.

In addition, in this build /postrollback scripts can be run in an admin context or a system context. This is useful because in some enterprises most employees don’t have admin privileges. So users can now run /postrollback scripts, even if they don’t have admin privileges.

There are also the usual minor changes, improvements and fixes, including one in which pressing and holding on a card in the new Timeline feature would open the corresponding app, rather than bringing up a context menu.

Windows 10 Insider Preview Build 17107

Release date: February 23, 2018

As Microsoft continues its sprint to release the next big Windows upgrade, it has stopped introducing new features, and new builds include mainly bug fixes. So this update is a minor one. It tweaks Windows Update behavior so that when an update is being installed on a PC with AC power, it stops the PC from going to sleep when not being used actively for up to 2 hours when receiving an update, so that the update proceeds more smoothly.

Beyond that are a variety of minor changes, improvements and fixes, including for a bug in which Settings crashed when users tried to open Themes, and another in which the Windows Defender offline scan had stopped working in recent builds. This update has a number of known issues, including the buttons on the Game bar not being properly centered.

Windows 10 Insider Preview Build 17101

Release date: February 14, 2018

The big news with this build is that it marks that the next upgrade to Windows 10 is likely now largely feature-complete. As Microsoft explains in its announcement about the build: “Right now our focus is on stabilization ... we intend to release new RS4 builds [previews of the next upgrade to Windows, code-named Redstone 4] to Insiders more quickly to both the Fast and Slow rings as these builds include mostly bug fixes.”

Microsoft is also “forking” its Windows Insider builds with this release — one fork is the one for the next upgrade to Windows 10, due to be released this spring, and the other fork is for what Microsoft calls “Skip Ahead” builds, previews of the Windows upgrade that will be released approximately six months after that, codenamed Redstone 5. This 17101 build serves double duty — it’s both for previews of Redstone 4 and the first Skip Ahead build for Redstone 5. However, the Skip Ahead build gets the build number 17604 instead of 17101.

Note that the Skip Ahead queue for accepting users is closed. People who signed up for the Skip Ahead RS4 builds starting in July 2017 and have remained in the Skip Ahead ring will get the Skip Ahead builds. But no new signups will get them at this point.

As for what’s in the build, it’s a relatively minor one. Some emojis have been updated and some Windows apps are being given broad file access permissions, although you’ll be able to turn that off if you want. In addition, the new edition of Windows called Windows 10 Pro for Workstations that in Microsoft’s words is “designed for demanding mission-critical scenarios targeting advanced users,” gets a few new features. The most important is a new power scheme called Ultimate Performance that gives as much power to PCs as possible but uses more power than other power schemes. Because of that, it’s not yet available on battery-powered PCs.

There’s also the usual assortment of tweaks, improvements and bug fixes, including an issue in which three- and four-finger touchpad gestures were unresponsive, and another in which Start didn’t work for Insiders who had added HomeGroup as a folder to appear on Start.

Windows 10 Insider Preview Build 17093

Release date: February 7, 2018

This build offers a wide variety of relatively minor new features. If you have a multi-GPU PC, you’ll be able to fine-tune how the GPUs are used, for example, to assign “power saving” GPUs to simple tasks like running your browser and using high-performance processing to run games. To do it, go to Settings > System > Display and scroll down to the “Advanced graphics settings” link. The build also lets more PCs play HDR video.

The build also tweaks the Diagnostic Data Viewer released in the previous build — Microsoft says it will now allow you to delete all the diagnostic data associated with a device. However, if you read closely enough, you’ll find that’s not the case. You’ll be able to navigate to a Delete button, but Microsoft notes that, “The backend cloud system is currently under development and will be available to complete the Delete requests prior to public release of RS4.” In other words, click all you want, but for now, the data won’t actually be deleted.

The “eye control” feature released in the Windows 10 Fall Creator’s Update gets some tweaks, so you’ll be able to use it more easily to scroll through content, navigate more quickly, pause and so on. Also improved is Windows 10’s Bluetooth capabilities, so you can pair with Bluetooth devices in a single click.

The build also tweaks the Edge browser a bit, so that in full-screen mode you can use the address bar, navigate to other sites, add favorites and more. New security features have been added to Windows, including account protection when signing into Windows. And the Game Bar has been given a makeover to make it easier to access all of its features, including new icons for muting a microphone, toggling recording and more.

In addition, users of Windows S, the stripped-down version of Windows designed for schools but available for everyone, will be able to log into the operating system without using passwords.

Aside from that are the usual assortment of tweaks, improvements and bug fixes, including updating the Windows Subsystem for Linux, redoing the Privacy Settings page and fixing an issue in which the Advanced display settings link was missing from Display Settings.

Windows 10 Insider Preview Build 17083

Release date: January 24, 2018

The big news in this release is a new set of privacy tools that let people see all the diagnostic data their devices send to Microsoft. The new Diagnostic Data Viewer lists all of the diagnostic information gathered, including Windows version, the ID of the device, connectivity information, performance and reliability data, app usage, installed software and more. You can scroll through each “diagnostic” event, as Microsoft calls them, or else search through them and filter them. You’ll also be able to fine-tune the level of data that Microsoft gathers.

To use the viewer, go to Settings > Privacy > Diagnostics & feedback. Turn on the Diagnostic Data Viewer toggle and click the button below it to launch the app. One warning about the viewer: The information it shows is extremely difficult to decipher and will be difficult for anyone other than programmers to understand. So the tool sounds more impressive than it really is. For a full description, check out the blog post “Microsoft introduces new privacy tools ahead of Data Privacy Day” from Marisa Rogers, the Windows Device Group’s Privacy Officer.

There's a variety of other improvements as well, including a new Fonts page in Settings that makes it easier to choose and use fonts. You’ll be able to see previews of each font, get more details about each font, fine-tune and uninstall them. Web developers and typographers get a variety of tools for tweaking fonts. In addition, in this build, you’ll be able to get new fonts from the Microsoft Store.

The Timeline feature has been changed as well. In this build, you can more easily delete activities from your Timeline. And Windows 10’s ease of access features get a variety of changes, including the ability to automatically turn on or turn off scrollbars.

Beyond that is an assortment of tweaks, improvements and bug fixes, including fixing an issue that could cause Windows to get stuck on the rebooting screen for a long time, and another in which Settings would crash if you tried to change the state of the microphone or camera permissions in Privacy Settings.

Windows 10 Insider Preview Build 17074

Release date: January 11, 2018

This build offers a variety of new features. Most of them focus on Microsoft Edge. Edge’s ebook reader gets a number of improvements, including a new look and feel based on Microsoft’s Fluent Design guidelines. The reader now provides a consistent interface whether you’re reading a PDF, EPUB book, or web content in Reading View. There’s also a new full-screen view. New grammar tools can highlight different parts of speech as well as break words down into individual syllables. And if you’re reading books purchased from the Microsoft Store, your reading progress, notes, bookmarks and annotations will more quickly sync across the devices on which you read them. If you’re having Edge read a book to you, it highlights words as they’re read.

Edge now stores credit card information and can autofill information on payment forms on the web. It also now supports CSS extensions for OpenType Font Variations, among other new features.

Windows 10’s Quiet Hours feature has been slightly tweaked. In the current version of Windows 10, Quiet Hours lets you turn off notifications between the hours of 12 a.m. and 6 a.m. In this build, you can customize the hours it works. Quiet Hours will also automatically turn on when you play games.

The Windows Settings app has been updated. In an attempt to consolidate settings of different kinds, the Disk Cleanup feature now can be found in Storage Settings, and the Sound Settings page has gotten a variety of minor tweaks.

Microsoft continues to work on better integrating pen input into Windows 10. In this update, you can tap a pen on any text field, and you’ll be able to input text using the pen. What you write is converted to text via handwriting recognition.

Beyond that are the usual assortment of tweaks, improvements and bug fixes, including fixing an issue where Settings sometimes crashed if the window was too small, and one in which Microsoft Edge sometimes crashed when deleting favorites.

Windows 10 Insider Preview Build 17063

Release date: December 19, 2017

This is a major build with significant new features. The main one is Timeline, which was supposed to be part of the Fall Creators Update but which Microsoft delayed because it couldn’t get it working properly in time. Timeline is a kind of time machine that lets you see what apps and work you’ve been doing in the past, then jump back to them at the point you left off. It will work across devices, so that if you start work on a desktop PC, when you move to your laptop, you’ll be able resume work without missing a beat. Eventually it will work with iOS and Android devices as well, according to Microsoft.

Timeline works as an extension of Task View, with past tasks shown onscreen in addition to your current ones. You’ll be able to switch among them by clicking on the appropriate thumbnails. You can look at past tasks from the current day or previous days, and move through them all with a scrollbar on the right side of the screen. You can also search for a particular activity. To control how Timeline works, go to the new activity history page in the Settings app. Cortana also works hand in glove with Timeline, recommending activities you can resume using the feature.

Microsoft

Timeline works as an extension of Task View.

All of Timeline’s features aren’t yet enabled. For now, it works with activities done in Microsoft Edge, Microsoft Office including Word, Excel, PowerPoint and OneNote, and updated versions of Maps, News, Money, Sports and Weather. It likely works with other apps as well, although not necessarily all of them, and Microsoft hasn’t provided a list of which work with Timeline and which don’t. To use Timeline, click a new Task View icon on the task bar, or else press the Windows logo key + Tab, which is how your normally run Task View.

Microsoft has been busy in this build; there’s more than just Timeline on tap. Also new is Sets, which add tabs to applications as a way for you to have various pieces of information in one place directly in the application itself. For example, if you’re in Excel, you could have a tab for your worksheet, another for a web page that has data you want to copy into the spreadsheet, and so on. Microsoft’s Dona Sakar describes it this way: “The concept behind Sets is to make sure that everything related to your task: relevant webpages, research documents, necessary files and applications, is connected and available to you in one click.”

Sets isn’t being delivered to all Insiders who get this update. Microsoft says it’s being released as a “controlled study,” but doesn’t provide details about how many people will receive it. Also, the name of the feature may change, and the way it works may change as well.

Microsoft Edge also gets improvements. Using Microsoft’s Fluent Design guidelines, it now supports a dark theme and has a variety of other minor user interface changes. Edge also supports the new Service Workers and the Push and Cache APIs Web standards, which let web pages send push notifications to the Action Center and refresh data in the background, even when Edge is closed.

Cortana, meanwhile, has gotten a few changes. The Notebook gets a new look, including a feature called Organizer that easily find your lists and reminders. Cortana now also lets you control Spotify using “natural language” to do things such as playing your weekly Spotify playlist, play specific tracks and more.

Fluent Design is being incorporated into more places throughout the Windows Shell, by applying its acrylic feature to the taskbar, Share UI, Clock & Calendar flyout, Network flyout, Volume flyout, and Input flyout. Acrylic lets developers add physical texture and depth to apps. Fluent Design also has been used to tweak the Settings app.

My People gets a variety of new features, including the ability to drag and drop contacts and rearrange them on the taskbar. You can also now decide how many contacts you want displayed on the taskbar — any number between one and ten. In the Fall Creators Update, you were limited to three.

There have also been a number of other minor changes throughout Windows, including the ability to use Paint 3D on screens you capture with the Snipping Tool. Emoji lovers will be pleased to know they can use the Emoji Panel in more languages. There are new privacy settings as well, notably one that lets you set global options for every privacy-related setting for microphone, camera and location access. That will let you disable apps and Windows from accessing these features on a device.

What IT needs to know: The build also has additions aimed at enterprises. The Windows Defender Application Guard (WDAG) will be included in Windows 10 Professional when the next version of Redstone ships. Currently, it’s available only in the Windows 10 Enterprise version.

IT will get some new features for optimizing the delivery of Windows 10, including new policies for Group Policy and MDM to let system administrators throttle bandwidth at specific times of the day, as well as being able to “restrict peer selection to the same subnet, automatically join devices into peer groups by using a DHCP server’s User option or the connection’s DNS suffix as well as the ability to increase the usage of peers by delaying the use of the HTTP source,” in Microsoft’s words.

The Windows Subsystem for Linux (WSL) gets a number of updates, including the ability to run background tasks and run when connected via OpenSSH, VPN, Enter-PSSession and/or other similar Windows remote tools.

Windows 10 Insider Preview Build 17046

Release date: November 22, 2017

This build includes minor feature changes, primarily improvements to the Windows Shell, including a simpler way to get to advanced options in Settings and an update to the way emojis are handled so that more of them appear when you type words related to them on the touch keyboard. In addition, Microsoft Edge can now save and automatically fill in preferred information in addresses and related forms. There are also many bug fixes, including restoring the Properties dialog for This PC in File Explorer to functionality.

Windows 10 Insider Preview Build 17040

Release date: November 16, 2017

This minor build includes only a few new features. Additions to Settings include one that lets you adjust the brightness of SDR content on an HDR display. Also new is the ability to use shape-writing input on the wide virtual keyboard. (Shape-writing for the one-handed keyboard was introduced in the Fall Creators Update.) The handwriting panel has also been improved, with a change to the insertion gesture and a new commit gesture. There’s also a long list of bug fixes, including an issue where network profiles had changed from Private to Public after upgrading to the previous build.

Windows 10 Insider Preview Build 17035

Release date: November 8, 2017

This build is the first in Redstone 4 to introduce a variety of new features. There’s a new sharing feature called Near Share, which lets you share URLs and files with nearby PCs via Bluetooth. Both PCs need to have Build 17035 or above, and both the Near Share setting and Bluetooth need to be turned on in both PCs. Microsoft Edge also gets several new features, including the ability to mute tabs playing audio, and new context-menus options for EPUB books. The touch keyboard now uses Microsoft’s Acrylic design standards, and there are also more than 190 new kinds of keyboards, including more languages and keyboard layouts. The handwriting panel can now better recognize words.

Included are also many bug fixes and minor additions, including updating Cortana collections to support light themes, and fixing an issue in which Store download errors were displaying on the Windows Update history page.

Windows 10 Insider Preview Build 17025

Release date: October 25, 2017

This minor build, an early one in the Redstone 4 release cycle, includes very few new features and changes. Ease of Access settings, such as for the Narrator, which reads onscreen text, have been regrouped and made simpler. Microsoft has also made changes to the Microsoft Yahei font used to display Windows user interface text in the Chinese (Simplified) Language so that it’s easier to read. Beyond that are the usual wide-ranging fixes, including one for not being able to scroll to the very bottom of the Start menu using touch when you are in tablet mode on small devices.

Windows 10 Insider Preview Build 17017

Release date: October 13, 2017

Because this is an early build in the Redstone 4 release cycle, there aren’t many new features or changes. Cortana gets a few new tricks, including what Microsoft calls Cortana Collections, which are things you’ve already expressed interest in, including restaurants, recipes, things you shop for, movies, TV shows and more. Cortana puts them into organized lists so you can choose any of them easily. The build also simplifies actions taken between Cortana and Action Center. There is also a wide variety of fixes, including an issue where changing time zones made the lock screen clock incorrect until logging out and back in.

Windows 10 Insider Preview Build 17004

Release date: September 27, 2017

This build is the first one to feature the 17xxx numbering system. Microsoft notes that the jump forward “is what we do normally at the beginning of development of a new feature update for Windows 10.” The build was done while Microsoft was getting the Windows 10 Fall Creators Update ready, so there are very few changes or new features. It shows off some of Microsoft’s Fluent Design look-and-feel, including Reveal, a lighting effect which is supposed to “bring depth and focus” to interactive elements. You’ll see it on the Start Menu.

Beyond that, there are a variety of minor improvements and bug fixes, including for one in Microsoft Edge where the tab previews for PDFs were black with a white bar on each side.

Windows 10 Insider Preview Build 16362

Release date: September 13, 2017

This build, as with the previous one, was created while Microsoft was getting the Windows 10 Fall Creators Update ready, so there are very few changes or new features. Bootup has been changed slightly, so you can see lock-screen customizations, such as whether you get status information from Cortana, before you log in. There have also been the usual miscellaneous bug fixes and minor improvements.

Windows 10 Insider Preview Build 16353

Release date: August 31, 2017

This build, the first en route to the Redstone 4 version of Windows 10, is an exceedingly minor one, with no new features. It fixes a very small number of minor bugs, including one in which the taskbar is unexpectedly thick if you booted up the PC while plugged in to an external monitor with a different DPI.